I don't know how much it costs to make a wrist watch out of a 12s pocket watch movement, but a couple points...
First, this is an open face movement (winds at 12:00). That means that you'll need a new dial that puts it at 3:00, and the sub-seconds dial at 9:00. You can find hunter case movements (winds at 3:00, sub seconds at 6:00) in the same size.
Second, this is Elgin's lowest grade of 12s movement, with 7 jewels. They also made them in 15, 17, 19, 21, and 23 jewels. There are A LOT of the 15 and 17 jewel versions out there, which are not only prettier, but also more durable, and less likely to have ovalized pivot holes which would make accuracy difficult to achieve.
Third, the steel parts that should be shiny look dull, possibly corroded. If they are, it'll take a LOT of work to make them look good, probably more in time and effort than it would cost to get another movement. Also, if they're rusted, the hairspring might be rusted, and if it is you'll never get good performance out of it.
I rather agree with GeneJockey: this will be a LOT of work, and may drive you a bit Crazy before you're done...proceed with Care!
There are such things as ( old!) USA-made 6size ww cases, that will allow a hunting movement to become a WW that winds at 3. They seem darn uncommon, but available...perhaps you'd be happy with a good-size watch that uses a 100 year-old, 6 size USA PW movement.
Take a peek over at Dave's Watch Parts. He is very good at finding material, and may well be able to set you up with a fine-quality movement & case.
Be patient and ask around...many things become Possible for those who know what they're looking for ( and are a bit Lucky! ).
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